1. Field of the Invention
The present invention relates to an ethylene-isoprene random copolymer, an elastomer composition and a cross-linked elastomer composition. More particularly, the present invention relates to an ethylene-isoprene random copolymer having a fast cure rate and a high crosslinking density, an elastomer composition and a cross-linked elastomer composition obtained by using said ethylene-isoprene random copolymer. The term "random copolymer" as used herein refers to a copolymer in which an arrangement of monomer units is random (see, "Essential Highpolymer Science", page 21, published by Kodansha, written by Seiichi Nakahama et al.).
2. Description of Related Art
Heretofore, JP-B-48-56775 disclosed a process for producing an ethylene-isoprene amorphous copolymer using a vanadium chloride compound, and an ethylene-isoprene copolymer having an isoprene content of 50-80% by mole obtained by said process. In addition, Dong-Ho Lee et al disclosed a process for producing an ethylene-isoprene copolymer using ethylenebisindenylzirconium dichloride (Et(Ind).sub.2 ZrCl.sub.2) modified methylaluminoxane catalyst system, and an ethylene-isoprene copolymer having an isoprene content of 0.9% by mole obtained by said process (Eur. Polym. Jour., Vol. 33, No. 4, pp. 447, 1997). However, no ethylene-isoprene copolymer having a fast cure rate and a high crosslinking density has been known.